Chapter 10.1 (Mathematics 5)

Cubic Centimetre

Identifying the cubic centimetre as a unit of measuring volume

In groups of five:

  1. Use plasticine or clay to make one centimetre cube such as shown below.
  1. Measure the sides of the cube to confirm that the length of the sides are 1 cm each. What is the volume of the cube?
     cm3
  1. Discuss and share your results with other groups.
  2. Make more 1 cm cubes.

Note

  1. A cube of sides 1 cm is called a one centimetre cube (1 cm cube).
  2. The space occupied by the 1 cm cube is its volume.
  3. The volume of a 1 cm cube is one cubic centimetre (cm3).
  4. One cubic centimetre (cm3) is a unit of measuring volume.

Exercise A

A1

In groups, use eight 1 cm cubes to make a larger cube.

A2

In groups, use the following number of 1 cm cubes to make cuboids:

  1. 12
  2. 15
  3. 24

Volume of a cube by counting 1 cm cubes

In groups of five:

  1. Use 1 cm cubes to form a larger cube as shown
  2. Count the number of the 1 cm cubes used to make the larger cube.
      cubes
  1. Discuss:
    1. The volume of 1 cm cube in cm3.
       cm3
    2. The volume of the larger cube in cm3.
       cm3
      What do you notice?
  1. Make other cubes with 1 cm cubes and find their volumes.
  2. Discuss and share your results with other groups.

Note

The volume of the larger cube is the total number of the 1 cm cubes.

Example 1

Find the volume in cm3 of the cube shown.

  1. The number of 1 cm cube in the one layer is 16.
  2. The number of layers are 4.
  3. Total number of 1 cm cubes is 16 × 4 = 64 cubes
  4. Volume = 64 cm3

Exercise B

1.  cm3

2.  cm3

3.  cm3

4.  cm3

Volume of cuboids using 1 cm cubes by counting

In groups of five:

  1. Arrange 1 cm cubes to form a layer of a cuboid as shown.
  1. Count the number of 1 cm cubes that make the layer.
     cubes
  2. Place another layer of 1 cm cubes on top of the first layer to form a cuboid as shown.
  1. Count the number of 1 cm cubes in the 2nd layer.
     cubes
    1. What is the total number of 1 cm cubes in the cuboids?
       cubes
    2. What is the volume in cubic centimetres (cm3) of the cuboid?
       cm3
  2. Make other cuboids using 1 cm cubes. Find the volume of the cuboids by counting.
  3. Discuss and share your results with other groups.

Example 2

Find the volume, in cm3, of the cuboid shown by counting.

  1. There are 4 layers of 1 cm cubes.
  2. Each layer has 8 one cm cubes.
  3. Number of 1 cm cubes is 8 × 4 = 32.
  4. Volume = 32 × 1 cm3 = 32 cm3.

Exercise C

1.  cm3

2.  cm3

3.  cm3

4.  cm3

5.  cm3

6.  cm3

7.  cm3